The invention generally relates to light armored vehicles having weapons systems located generally on the upper portion of the vehicle. A turret shell or a cupola supporting the weapons system rotates on bearings to enable movement of the weapons system throughout a 360 degree arc for firing on any target at any position relative to the light armored vehicle. Suspended from the turret is a turret basket which typically has two seats, one for a gunner and one for the commander to operate the weapons system as well as other elements within the vehicle. A drive system for rotating the turret and turret basket employs a motor, a pinion gear and ring gear assembly to drive the pinion and ultimately the turret through the desired arc.
Heretofore, azimuth drive systems, at least to a certain extent, have been characterized by their complexity, inefficiencies, inadequate provision for maintenance access, and manual backup. When a backup system has been provided, it has been unusually complex, often rendering it somewhat inefficient and not dependable.
The invention described herein overcomes many of the problems discussed above. The manual backup system in the invention described herein includes a disconnect apparatus for disconnecting the motor and connecting the manual portions of the apparatus for driving the pinion gear. This disconnect apparatus includes an exposed handle which is simply pressed by the operator from its normal position and rotated to lock the disconnect apparatus into an operative mode so that the pinion gear for driving the turret can be rotated manually. This system is spring biased to the inoperative mode such that, when the handle is unlocked, the system will automatically retract to the inoperative mode. By disengaging the manual apparatus in this manner unnecessary loading on the motor is largely eliminated, thus enhancing the efficiency of the motor when in operation. On the other hand, when the motor becomes inoperative for whatever reason, the manual apparatus can be connected quickly and efficiently by movement of the handle.
The hydraulic motor, which preferably is a ball piston type, employed is characterized by an internal relief mechanism such that it is not back loaded when the manual apparatus is in the operative mode. In other words, the motor will automatically revert to a "destroke" or no load operation thus avoiding the need for clutches or other mechanical connecting means.
Furthermore, the system described herein achieves minimum backlash, precision movement with economy and efficiency which is lacking in prior art systems. In addition to the type of hydraulic motor, and gear box chosen, which preferably is a circulate reducer, these features are achieved by spring biasing the pinion gear against the ring gear on the vehicle body. This permits the system to be self adjusting and accommodate eccentricities in the gearing system.
The above has been a general discussion of certain advantages of the invention described herein and deficiencies which have been noted in drive systems used heretofore with armored vehicles. Other advantages will be perceived in the detailed discussion of the preferred embodiment which follows.